How do mice cope with heat? - briefly
Mice lower body temperature by vasodilation of skin vessels, frequent licking to enhance evaporative cooling, and relocation to shaded or ventilated areas. Extended heat stress induces heat‑shock proteins that stabilize proteins and cellular membranes.
How do mice cope with heat? - in detail
Mice employ a combination of behavioral and physiological strategies to maintain homeostasis when ambient temperature rises.
Behavioral adjustments include seeking cooler microhabitats such as shaded areas, burrows, or nesting material with higher thermal conductivity. Activity patterns shift toward the cooler phases of the day, reducing exposure during peak heat. Increased water consumption supports evaporative cooling through licking of the oral cavity and paw pads.
Physiological responses involve several mechanisms:
- Peripheral vasodilation expands blood flow to the skin, enhancing heat dissipation.
- Respiratory rate rises, facilitating convective heat loss via increased airflow over moist respiratory surfaces.
- Sweat gland activity, though limited in rodents, contributes marginally to evaporative cooling.
- Heat‑shock proteins (HSP70, HSP90) are up‑regulated, stabilizing cellular proteins and preventing aggregation under thermal stress.
- Metabolic rate adjusts downward, lowering endogenous heat production.
- Hormonal modulation, particularly elevated corticosterone, influences energy allocation and stress resilience.
Acclimation to prolonged high temperatures results in structural changes such as increased capillary density in the dermis and altered expression of thermogenic genes. Experimental data show that mice exposed to chronic heat stress exhibit reduced core temperature set points and enhanced survival rates during acute heat challenges.
Effective thermal management in mice therefore relies on coordinated shifts in habitat selection, activity timing, fluid intake, circulatory dynamics, respiratory ventilation, molecular chaperone expression, and metabolic regulation.